P1030989 copy

It’s kinda late, but I just turned a Schoeps CMC4U preamp into a CMC5U

A CMC4U preamp from Schoeps won’t see much use these days, as “T” powering becomes less available, less popular, and technically antiquated.  What a waste!  Not wanting to destroy a perfectly functioning (and expensive) condenser mic preamplifier, this was approached with some careful deconstruction and if things went awry,  a planned exit strategy to salvage the T-power.   Planning, measuring, parts accumulation, head scratching, a couple of bad dreams and lots of solder smoke resulted in a CMC4U-turned 48 volt phantom-powered CMC5U. To our ears, it is indistinguishable from the CMC5U. This project’s been on the shelf for over 2 years, so we are happy it’s complete.interior

 

Now for a few shoot days to  beat it up in the field to make sure the mods hold. It takes about 9 component additions/changes, a some trace cuts, and a couple of trace bridges. Matching some component pairs, and some delicate rewiring , so you don’t melt anything or break component leads. Removal and replacement of silicon stabilizer, as some of the components are covered in it. Very good soldering and wiring skills required, and the ability not to over-work component leads or lift traces.  Anyone interested, see www.cmc4upgrade.com

by Pete Verrando

seebpic1

Seeburg 1000 “Window Unit” Background Music Player restoration

A recently edited presentation of our Seeburg 1000 BMC player. We call it the “Window Unit”

Seeburg 1000 players employ special 9″ records with 2.5″ center holes. The device plays both sides of each record, then lifts the stack to the top of the spindle for replay. Seeburg BMS (background music systems) were In widespread use in department stores, restaurants, and other retail and industrial locations from the early 60’s through the late 70’s. They have become very popular mid-century modern artifacts.   The thousands of  music selections were individually crafted by professional musicians and studios, and are utterly representative of  a unique and often forgotten part of American culture.   The 16 rpm records are widely available on ebay.

This is my 4th complete restoration of a Seeburg 1000 player.  Thanks for watching!

-Pete Verrando

A saga of Kentli Lithium-Ion 1.5 volt AA rechargeable cells.

Many folks are very excited to see the first rechargeable Li-Ion AA battery, made by Kentli. 

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Kentli AA Lithium-ion rechargeable cells and charger.

 

 Here’s a cut-away view of their exciting new AA cell:

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The guts of a Kentli Cell.

The Kentli AA Lithium-Ion cell was perceived as an exciting development, because all Lithium Ion cells are normally 3.7 volts. So even if the cell could fit into the AA form, the voltage was too high for 1.5 volt applications.  What Kentli did was cram a 3.7 volt Lipo cell into an AA enclosure, and also stick a 3.7volt-to-1.5volt regulator inside there as well.  The charging groove (see diagram) allowed the cell to be charged directly by the charger at 3.7 volts, bypassing the “motherboard” (regulator).

Why would we want a Li-on AA cell, anyway?  The perceived advantages:

1. Ni-mH cells, the current rechargeable of choice, provide only 1.2 volts per cell.  That missing 3/10ths of a volt can really add up when using multiple cells in series (battery)! The lower voltage also increases current draw, shortening the power-up time of the cell.

2. Lithium Ion cells maintain almost their rated voltage right up till they die  Other cells, the voltage slowly drops as the cell discharges.  Many digital devices will shut-off when the supply voltage falls to a certain level, leaving much potentially live-giving energy in the cell.

3. For their weight, Lithium-Ion cells currently provide the most deliverable power than any other type of cell. They charge fast, are very reliable, and last for many charge cycles. They are also tolerant to recharging at various states of discharge.

More Advantages:

4. Rechargeable batteries create less land-fill waste.

5. Rechargeable batteries create incomeas you can bill the client for these batteries like disposables.  So, they can routinely add about $20 or more to your daily rental income, without buying disposable batteries.  Over a year, that can add up (conservatively) to about US$3000. (that’s if you work only about 14 days a month as a professional location sound mixer)

So how well do Kentli Li-ion AA cells work?

As Chinese Industry is prone to do, Kentli did some slight-of-hand marketing with these products. They listed the capacity in milli-watt-hours, so they could print that big 2800 mWh on the side of the cell.  For people who don’t pay attention, this rating gives the mistaken impression that they are more powerful than 2700 mAh (milli-amp-hour) Ni-MH rechargeables. 2700 is a common value when looking for a high quality Ni-MH rechargeable.  At 1.5 volts, 2800 mWh translates to about 1867 mAh,  so the Kentli cell technically has less power. But Kentli claims their cell lasts as long as the Ni-MH, because the regulator allows the 1.5 volts to be maintained till the cell is completely exhausted.

The street price for these Kentli AA cells is about US$11 per cell, and the charger about US$20. More expensive than Ni-MH rechargeable. They are shipped directly from China through a few distributors, including sellers on ebay.

 

lectrosonics smv verrando txsound

A Lectronics SMV transmitter. 1/3rd of the package is for the cell.

We bought 12 AA cells and 2 chargers to give these units a workout in our Lectrosonics SMV transmitters.  The SMV uses only one AA cell.  A disposable Energizer Lithium AA will power it for 5 hours (the longest). The best NiMH rechargeable will power it for about 3.5 hours.

And the result? A fresh Kentli AA, right out of the box ,will power the SMV for 3.5 hours. Same as a high quality, 2700 mAh Ni-MH rechargeable.

But here’s the rub, in a few easy steps.

1. In my application, Kentli AA’s take their internal cell from a full charge to near-exhaustion in every cycle. Over the long term, I think Li-Po rechargeables prefer a lighter charge-discharge cycle. so with this workout, these Kentli cells won’t last for very many cycles. A Lectro SMQV would treat the cells more gently, distributing the current draw between two cells, and possibly resulting in better performance.

2. Kentli AA’s use a 3.7v Li-Po cell and convert it to 1.5 volts. There is inherent inefficiency in this conversion process.  The Lectro SMV then takes the 1.5 volts and inverts it up to 5 volts, and 3.3 volts, to serve the various internal functions. Every time you convert a voltage, you lose some efficiency and power, in the form of heat.  The Kentli is already stretching the capacity to the max of its tiny 3.7 volt, 760 mAh cell, every time it is charged and used. With the SMV, there are multiple conversions, and those power losses add up.

3. These days,  the “power down” mode of many devices is not a true power-down. Even after its turned-off, the SMV draws a tiny “quiescent current.” This is simply power to enable the SMV to power back up with a momentary button-push. The Kentli sees this quiescent current, and therefore keeps its motherboard alive, affecting a continuous drain on its cell. So leave a freshly charged Kentli in the SMV overnight, and it will be dead in the morning.

4. Maintaining AA rechargeables for location sound use is a pain in the ass. They get lost easily. I lost one in the snow on the very first shoot! They are difficult to keep separate between used and unused. They require chargers to be travelled and plugged-in. They require extra time to sort and charge and check at call and wrap.  They create a level of uncertainty in the production process. Will this be the shot when the battery dies for good?

5. And obviously, in the SMV, a rechargeable will run for only 3 hours, and a AA li-ion disposable will burn for 5 hours.  In most cases, 5 hours is enough time to get us to lunch, when the battery can be replaced.  The SMV is designed to accept a cell that swings from 1.9 volts to .9 volts, and before it dies, will suck every last ounce of power from the cell!

6. Don’t talk to me about the Lectro SMQV, the double AA version. I know they will run twice as long. I don’t care. I like the smally-small SMV for so many reasons. I use it as a drop-weight when running the lav cable down shirts and blouses and pant-legs. The SMQV is almost as large as a UM400A, Lectros classic 9-volt transmitter, of which I already have a shit-ton.  The SMV is great for use on children, with their tiny pockets and elastic waistbands. It also has the lowest profile in a pocket or bra-strap.

Oh, and the Kentli Chargers tend to die. 

kentli charger txsound

The Kentli Charger with its ring-groove contacts. They contact directly with the Li-Po battery and charge at 4.2 volts.

kentli, location sound mixer, txsound.com

The innards of the Kentli AA charger

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A 5 volt phone charger inserted into the 5 volt rails of the Kentli charger. Fixed!

Of the two Kentli chargers I originally ordered, one died a couple of months in. The dealer asked for photographic proof that the charger was dead. They sent a replacement from China, which never arrived, and then sent me another.  Eventually I received both chargers, so now I had four. Then the other 2 chargers immediately died.  Taking this opportunity to either throw away the dead chargers, or take them apart, what do you think I did? The charger consists of a very flimsy switching power supply converting your AC house current to 5 volts DC. The voltage is then applied to a smart charging circuit for the AA cells. The flimsy switch-mode supply was the obvious culprit, so it was replaced with an outboard 5 volt phone charger, of much more robust design. So now we have 4 chargers.

 

Then, the Kentli AA’s start to show signs of age.

This is about the time that the Kentli AA cells stopped delivering 3 hours of power to the SMV’s.  This is not the cell you want in a transmitter that goes out on a competition shoot, where you don’t have access to the talent once the action begins. I would guess I got about 100 charges on my Kentli’s before they began to show signs of expiration. The chargers show a full charge even on the cells that have stopped performing. In a less-demanding environment, (like an LED flashlight or an ipod dock) they may give better service.

And Alas! one Kentli drops to the floor and pops open like a Zippo Lighter! (Also the shrink wrap on the cell will begin to tear and peel with daily use. )

kentli AA txsound.com

Pops open like a Chap-Stick!

kentli txsound sound mixer verrando

The Kentli regulator board.

UPDATE : Curious about the quiescent current draw of the Kentli Cell, on its own, we hooked up a micro-amp meter between the regulator board and the Li-Po cell. The result:

kentli AA self discharge txsound

Kentli AA cells discharge on thier own, with a constant current draw of 29 microamps from the internal “motherboard.”

You guessed it. The Kentli motherboard is drawing 29 microamps from the cell at all times.  By comparison, Lectro transmitters, when powered down, draw about 5 microamps from the cell.  This is in conflict with the advertising claim made on the Kentli promotional material:

discharge claim kentli txsound.com

Advertising claim from Kentli’s promotional materials

 P1010251And whats this? A 3.7 volt, 2.66 wH li-po cell! That’s 2660mWh, or 718 mAh! Not 760 mAh, as the label claims!

So there’s no doubt the Kentli folks are really pushing the envelope with this initial attempt at a 1.5V Lithium-Ion rechargeable. A little more conservative design paramaters are required for location sound use. But for flashlights and home use, I’m sure theres no telling! And no telling of what’s to become of my little AA canisters for a location sound mixer on the road!

16" transcription record

Presto T-68 16″ Transcription Turntable Restoration

 About 3 years ago, I saved the pieces of this 16″ transcription player & cabinet from a dusty internment.

The 16" platter, stripped, cleaned and ready for re-felting

The 16″ platter, stripped, cleaned and ready for re-felting

presto turntable

cabinet as found

16" presto turntable

Project in pieces before restoration

Presto top plate with idlers removed.

Presto top plate with idlers removed.

 

 

 

busy day at txsound

busy day at txsound

 

 

(Click the thumbnails above for a larger “before” view). ,  This Presto T-68 Transcription Turntable with Pickering 190D Tonearms was used at an Air Force base in Fort Worth. Found inside the cabinet was a 16″ acetate record, with the lacquer falling off the aluminum substrate. The disc labels indicated the acetate had various Reveille bugle calls, marching and teletype sound effects. The military base had its own radio station, or perhaps they used these effects over the public address system for PT!

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The acetate found in the cabinet.

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Old Acetate disc labels from in bottom of turntable cabinet

 

 

 

 

 

 

 

 

 

Upon complete disassembly, work started on the motor & start capacitor, with a gentle variac power-up to check for shorts in the windings, or a bad capacitor.  It’s an an Ashland Hysteresis Synchronous motor of 1/100 horsepower. after a complete overhaul, the motor ran continuously for a couple of days to observe operating temperature, let the bearings settle in,  and discover any latent noise or vibration issues.  New motor mounts were installed as well.

Ashland motor presto turntable

Motor removed for teardown, old lubricant removal, reassemble and re-lubricate. Slow power up with variac.

Three rubber idler wheels transfer the motor’s energy to the platter at 78, 45 or 33 1/3rpm, depending on which plane of the spinning motor shaft is engaged (see photo below).

presto t-68 idler wheels turntable txsound

Transport with Terry’s new idler wheels installed.

The existing idler wheels (above) were hardened and crumbling. The brass hubs were re-surfaced by Terry’s Rubber Rollers. The motor and idlers get the platter up to speed in about 1/4 of a platter rotation. Pretty quick, which was important for the operators ability to tightly cue the audio tracks.  

The tonearms are type Pickering 190D, originally wired for mono.  BTW, Mr. Pickering holds the original patent on the moving magnetic phono cartridge!  These tonearms were heralded for extremely low vertical to lateral moments of intertia, and minimal vertical mass.  Because of the big swing of a long tonearm, the tracking error is less than 2.5 degrees.

pickering 190D tone arm

Pickering 190D tonearms, mono wiring & magnetic arm rest.

pickering 190 txsound verrando

The Pickering 190D (click/enlarge)

The tonearm’s extremely low head-mass  can deftly handle a warped record very nicely.  The rear tonearm is intended for a 78 rpm cartridge/stylus.  The front arm is for a microgroove cartridge.  A top- mounted rotary switch selects which arm is fed to the pre-amp.  Before restoration, the signal passed through a Pickering model 132E passive equalizer before being pre-amplified by a mono model 230H Pickering tube preamp.

 

 

pickering 230H preamp. txsound

Ad for the original preamp. (click/enlarge)

pickering presto

Pickering passive cartridge equalizer.

presto tonearm selector

78- LP tonearm selector

presto power switch

Power switch with a hand-made plastic mount-plate

 

 

 

 

 

 

 

 

 

Both  tonearms get re-wired for stereo, no small task with hair-thin oxygenated tonearm wire. The rotary switch was replaced to enable stereo switching between tonearms. The mono Pickering equalizer was removed(which will fetch about $100 on ebay) and the resulting empty hole with a bat-handle power switch for the motor, a more practical use of the space.   The turntable previously was powered-up when the speed selector was enabled. A  black switch mounting plate was created to match the other label plates on the plinth.

 

 

A new stereo tube preamplifer is now required inside the cabinet, so a Little Bear Stereo Valve Preamp was shipped in from Hong Kong.  (below)

 

Little Bear Presto Pickering

The popular Little Bear stereo tube pre-amp from Hong Kong.  Very nicely designed!

 

presto rca patchbay txsound

RCA patchbay on rear panel.

 

To allow the user to select the internal or an external preamp, An RCA patch bay  is added on the rear cabinet panel. Also shown is the ground lift switch, power connector and chassis ground terminal.

 

 

 

 

 

 

 

pickering presto turntable txsound

Assembly and wiring of tonearms. Individual Channel signal/ground wires eventually made into twisted pairs for hum suppression.

 

The cabinet was a challenge, especially the plinth. The 3/4″ plywood base surface was covered in a thick, ancient, funky, dull- green laminate. The surrounding metal was painted industrial grey with a good deal of chipping & corrosion. The metal surrounding the laminate was refinished in hammer-tone grey .  The funky-green clashed with the other colors, so the wood top was refinished in solid satin black.  The platter had plenty-enough green in it after the re-felting, which is done with felt, spray adhesive, and careful lathe-style trimming with a razor. The plinth’s vertical edges were stripped down to the bare metal and polished to a bright shine, almost chrome. The polishing process was observed in a motorcycle restoration shop, and has been sucessfully used here on lots of projects.  (Enlargable thumbnails below)

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2014-07-04_13-36-10_96 2014-07-04_13-36-41_12 2014-07-04_13-41-56_855 2014-07-03_12-46-10_159 2014-07-17_21-07-16_881

 

 

 

 

 

 

 

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Collection of 16″ transcription records are stored inside the cabinet. Those suckers are heavy.

 

The Presto- DuKane cabinet, preamp and associated wiring came together as pictured. The tonearms get fitted  with  Shure M91ED cartridges, the rear cartridge with a 78rpm stylus. The unit is extremely well grounded, including the motor shell, and cabinet ground is independent of signal ground. Wether using the internal or an external preamp, there are no hum issues. As a precaution, a ground lift switch was added to the rear panel.  Power lines are capacitor bypassed at the entry points and at the power switch.  (below pics are enlargeable)
P1030664h presto4h presto17H presto19h presto20h

 

 

 

 

 

 

 

The table adds a special allure to vinyl activities. A heretofore ignored  pile of 78 rpm records have provided some very interesting listening!  It’s the record industry in its infancy. Various recording techniques can be discerned, qualities, different equipment eras, groove depth variances, etc can all be heard.

 

 

 

 

presto turntable t-68 transcription verrando txsound

 

There’s a million cheap 78s, lps and 45s still floating around out there, in thrift stores, estate sales, and flea markets.  Many found 78s  have never been played, and those make for remarkable listening. Back in the day, the commonly used steel needles would destroy a 78 after 20 plays. Many outstanding shellac records are still out there, They are remarkable examples of recording skills and standards through the era.

 

presto transcription vinyl txsound pickering tonearm trans.com txsound

The 60’s produced some remarkably well mastered LP’s as well.  I particularly like the Command 35mm series, which are still in plentiful supply at the above mentioned sources. See you at the Goodwill!

MORE ABOUT TRANSCRIPTION TURNTABLES….

In the US, professional transcription turntables were primarily made by RCA, Gates, Fairchild, Presto, and McCurdy in Canada. They also required a separately purchased  “transcription” tonearm, about 3″ longer than a standard tonearm. The extra “swing room” these arms create also reduce stylus tracking error, especially on 7″-12″ records.

I’d been searching for a 16″ transcription turntable for many years. These tables are a unique and dissappearing part of broadcasting history.  Unlike a 12″ platter, they can  accommodate vintage 16″ transcription vinyl records, popular in the radio industry through the 50’s, 60’s, and 70’s. Amazingly, for their size, these records only contain about 15 minutes of program material per side!  That’s because the grooves are spaced far apart. The discs typically cannot fit on a standard 12″ turntable platter without hitting the tonearm base. The US Armed Forces and Veterans Administration used these records extensively to distribute their radio programs. The records also were popular for distributing library music, jingles and commercials.
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RCA 70 transcription turntable. Thousands of these used to reside US radio and TV stations.

Beardsley.press

A 16 inch record press

 

Gates transcription turntable txsound

Earliest version of the Gates CB-500 Transcription turntable.

The big turntables often came mounted on a cabinet, the size of a dishwasher. The earliest tables used this space for a complex, gear driven, flywheel-stabilized motor, These motors provided the necessary torque required for slip-cueing records and fast startup rotation.  Eventually, the torque came from smaller, hysteresis sync motors with idler/puck drives.  By the early 60’s these became the standard turntable design for radio/tv stations. In the early 80’s, Technics Corp. introduced powerful, direct drive, crystal controlled motors. They were adopted quickly by radio stations and used until CD’s replaced vinyl entirely…

rcaTTunderside
Huge flywheel motor affair that is under the platter of the early RCA transcription turntables.
Maybe there's still some hiding out there, somewhere?

Maybe there’s still some of these hiding out there, somewhere?

RCA BQ-2B 04

A more recent underside of a transcription turntable, the RCA BQ-2B. I do not recommend placing a tube amp in the cabinet!

 

 

 

 

If you’ve got room in your listening area for one of these behemoths, you’ll find them few and far between, and priced outrageously. And that’s before the freight shipping required to send to your place.  The most current and popular transcription unit is the Gates CB-500 ,  and the cabinet (if you can find it).

The Gates CB-500 and cabinet. The Holy Grail? This one's in Russia! The front panel controls are a sloppy, abortive add-on. 

The Gates CB-500 and cabinet. The Holy Grail? The front panel controls are a sloppy, abortive add-on.

 

 

 

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Grey Research Viscous Damped Tonearm with installation template.

 

 

 

 

 

 

 Personal Story Time: In my college days of Radio and Television (circa 1980), the school had a large, 3 camera TV Studio, with a huge cyclorama curtain surrounding the walls.  One day, while scrounging behind the curtain, I found two of the huge RCA transcription turntables, in their massive cabinets. They had the coveted Grey Research Damped Transcription Tonearms, so named, as the arm rode on a layer of oil to isolate it from the turntable’s vibrations. And also to minimize lateral friction. The RCA tables were in deplorable, but restorable condition. Piles of 16″ records cluttered the space around the machines. I had little interest in vintage gear in those days, and forgot about them.  20 years later, I  learned l that when the TV studio was renovated into a dance studio, the turntables had been unceremoniously trashed.  Truthfully, over 30 years later, I still have lucid dreams about finding vintage broadcast equipment in the bunkers and catwalks of my alma-mater’s fine arts building.  – by Pete VerrandoMeadows_School_of_the_Arts

Robocop Memories- Callsheets, Scripts, Photos, Comics, Video

robocop, Dallas, 1986,pete verrando, In 1986 I was a new freelancer in Dallas, TX, and was hired to assist with on-set video playback for Robocop. I had never been on a movie set prior to this, my experience limited to industrials, tabloid television and the like.  This was a new world for me. I’ve recently came across a stash of items I had saved from those days-  callsheets, photos, scripts, etc., so I thought I’d post a few here.   I ended up providing this “24 frame video service” to about 40 motion pictures shot in Texas throughout the mid-80’s to mid-90’s. At the bottom of the article is my video demo reel from my playback days.

Video Playback” was a position similar to music playback on a set. Except, I was working with videotape or providing computer & camera feeds. These sources fed televisions, monitors or computer screens in the camera frame.  The sound department often pulled a feed from the video, and I was tasked with hitting the playback on cue with what the actors were doing on set. I also sychronized the film camera to the video. The film camera had to be in-sync with the TV screens, or the 30 frame screens would flicker against the camera’s 24 frame shutter. Interfacing and controlling the camera dept’s raison d’etre  called for technical competence and diplomacy.

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The Boardroom were Murphy blows away Jones. Notice ED209 hiding around the corner!

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The VTR’s used to feed the boardroom monitors in the final scene.

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Sound Mixer Robert Wald’s, C.A.S. sound cart on the set of Robocop. Notice the FM radio headsets used for Comteks in 1986. Vega wireless, Stereo FM Pilot Nagra. This was the first “location sound cart” I had ever seen.

ed209, robocop, verrando, video playback, sound mixer

ED209- the life-size model present on the set of Robocop.

Robocop, video, board room, murphy, verrando, production sound mixer, blog

The 2nd to last page of the Robocop script- boardroom scene

Robocop, murphy, board room, video playback , verrando, texas location sound mixer

Last page of the Robocop script where Murphy shoots Jones in the boardroom.

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Call Sheet from Robocop – 1986- hand-written in those days!

robocop, call sheet, 1986, film, verrando, texas location sound mixer

The primary cast of Robocop, as listed on the call sheet, with their call times.

Robocop, call sheet, ED209, comics, verrando, texas production sound mixer

A little set humor was added to each day’s call sheet on Robocop, 1986.

Here’s the demo I would peddle to various productions when they came to Texas. “Need any video playback?” Productions were surprised when they learned the service was available in Texas!

Quadra-Quark Speakers

 

I’ve had a “stereo” of one kind or another since I was 10 years old. Does anybody even call it a “stereo” anymore?  Is there a human connection with stereos, like there is with cars?

vintage zenith portable record player

Restoration of a Zenith Portable Stereo, found for $5. Now in a San Francisco boutique.

So, I was basically hatched in the radio business. There, the day-to-day “fidelity” of what you are working on is just an afterthought. Either something sounds good, or it doesn’t. If “Fleewood Mac’s Rumors” got cue burn, you threw it away and pulled another. The tape heads weren’t cleaned until the grease pencil gunk got under your fingernails. When I was 26, everything sounded pretty damn good to me anyway.

sally diamond q102 dallas

My wife-to-be, 1986, clogging up the heads with white grease pencil

Recently I put together an odd assortment of components for my living room Hi-Fi.

. I’ve always been head-slapped at the revolutionary idea of 2 or more satellite speakers and a subwoofer. Why this idea had not been introduced into the personal listening space sooner is beyond me. For 50 years, manufacturers have been trying to make speaker cones bend in physics-defying ways in order to reproduce music from a single source, or two sources, woofer/tweeter, or stereo. I guess Western-Electric was doing bi-amped systems all along, but they were mostly in movie theaters.

So I rounded up a decent Altec computer speaker system consisting of two satellite speakers and a subwoofer. I got it a couple years back on Woot. for $49.

Ugly Satellite speaker enclosures must go.

Ugly Satellite speaker enclosures must go.

I mixed these components with a mono tube amplifier (6L6) push-pull and an extra large full-range ceiling speaker, in its own enclosure. The subwoofer and the ceiling speaker are on the first floor.  Add a tiny Behringer mixer for the mono sum and routing, and an abandoned TV cabinet.

motorola zenith stereo location sound mixer pete verrando

A 1950’s Motorola TV Cabinet. The front controls are tube power, tone, volume, subwoofer power, and sub volume.

Oh, and those ugly little Altec black plastic satellite enclosures will have to go. In with some 1950’s police squwak boxes.speechmasterjensen speechmasterjensen2

jensen speech master

Police Squaak boxes found at swap meet. Jensen Speech Master 4″ communications speaker.

Here they are post-restoration:satellitespkrs

satellitespeakers

Restore the speakers and the tv cabinet, stuff the amp, speaker and mixer in, drag it in the living room, put the little speakers on the mantle, and plug it in…..

I haven’t sat down and listened to a record in a long time. Having been raised listening pop music production values, I tend to go there when auditioning sound systems.
I spent quite a bit of time balancing the tube amp with the computer speaker system, while listening to to Steely Dan’s “Aja”.

Its kind of fun running a tube amp, and this one adds lots of volume to the system, and takes away some of the mid-range and bass chores from the subwoofer. Is also got nice glowy glass.

Well, it sounds very nice, for what it is.
The last time I had something nice in the living room for playing music, was before the kids were born. And with kids, all you end up using your hi-fi for is playing Raffi records. God help ya’ll with young kids. Get behind me, Satan!

My main conclusion about my little system is that there seems to be a “wall” just outside the satellite speakers. It sounds nice seated in the middle position, its even loud, but the room doesn’t fill up.

I guess the big advantage to an exceptional stereo system- is that it interacts with the room. You are surrounded with sound, but not just from multiple little speakers- you are surrounded with room reflections.

Then I put on some opera (Cecilia Bartoli), hoping for the walls to go away. And they sort of did, because I was no longer listening to a 24 track studio production of highly isolated instruments, like on “Aja.”

Trying different sources, one thing I noticed was how horrible any music from Pandora sounds. Its take awhile, but I’ve finally, finally developed a real disdain for digital compression. CD’s sound good to me, but I’ve found MP3’s and any other similar scheme really fatigues my ears. I can’t listen to music for very long when its compressed. It starts to get irritating, like when there’s young kids in the room.

I still have the stereo I got as a teenager! A Pioneer SX-450 receiver when I was sixteen. And, a pair of Frazier Mark IV speakers, built in Dallas, Texas. These hang from the ceiling in my office, and take all sorts of abuse from the buzzes beeps and crunches when I’m testing audio signals. But they hang in there. In my office, I’ve been playing a lot of Seeburg background music while I toil away.

SX-450 Receiver

SX-450 Receiver

frazier

Frazier Speakers made in Dallas, Texas.

I’m a sound man, not an audiophile.  -By Pete Verrando www.txsound.com

The Allure of Nagra Tape Recorders

Nagra IV-S tape recorder

Nagra IV-S Stereo Tape Recorder

Particularly regarding the Instrumentation Nagra SJ, an audiophile client was asking me what made the Nagra sound “special.” The SJ has “extended frequency response” to allow for measurment of vibrations and supersonic artifacts. Does it sound better? Is it the amplifier design?

Nagra III tape recorder 1960

This 1960 Nagra III has unusual head shielding. Also there is no tone generator or BA (before/after) switch.

The SJ is not necessarily going to sound better. The SJ recording system did not include the same pre-distortion tricks that are employed in the audio Nagras. As you go up in record level, saturation and non-linearity increase. Pre-distortion served maintain that linearity. Otherwise, the SJ has NAB/CCIR record and playback EQ like any other Nagra. The head gaps on the SJ’s were narrower, to allow for higher frequency recording and playback at 15ips. The specifications have the response at 35khz at 15ips. ….Nagras were often built to order, with unique circuitry combinations based on what the individual customer needed. Along with circuit improvements/changes done at the factory, (many undocumented) there’s hundreds of different Nagra configurations. There were even Nagras built without a front meter or input level controls, just a blank panel (Nagra IV-ML) These days, every Nagra I encounter is different in some way from the norm.

Nagra IV-ML

The Nagra IV-ML had no front panel meter or level controls.

nagra IV-ML

The levels were meant to be controlled at the mixer.

The Nagra playback amplifiers are simple, discrete transistor designs. I’ve had clients who own outboard tape head pre-amps they’ve paid $4000 for, like the “King Cello” preamp, so they want the outputs of the heads available on the side panel of the Nagra. For example see http://www.reeltapes.net/kingcello -one of these expensive preamps.

King Cello Nagra

King Cello Tape Head Preamp- $4000

Using the Nagra in a home music playback environment goes beyond the sound of the internal amplifiers. Users also appreciate having a very unique, professional, portable recorder. Stereo Nagras sold back in the 80’s for around $10,000. The build quality is remarkable, with no stamped parts, only machined aluminum/stainless steel parts. The functionality and durability were designed to withstand constant use in extreme environments and temperatures. The servo motor speed control can maintain perfect speed while the recorder is dropped to a table, or while the user is running on foot with the recorder on the shoulder. The tape tension mechanics are ingenious, continually self-adjusting tape tension during transport operations. The aesthetic design is a direct reflection of Kudelski’s sensibilities, from the unusual dual-needle meter, to the use of excessive panel labeling. Kudelski’s electronic designs were not complex, but all component values, tolerances and other characteristics were carefully regulated. All transformers and inductors (using toriod cores only) are wound entirely in-house. All fasteners are made of stainless steel. It is a laboratory-grade instrument that found its primary home in the alternative universe of motion picture production. That the film art-form once required such elegant, yet precision equipment is part of the Nagra’s allure. -by Pete Verrando www.txsound.comNagra IV-S Verrando  

Why I like Sennheiser G2/G3 systems for everything but talent wireless

sennheiser G3 wireless

Sennheiser G3 wireless microphone system.

Here’s just a few reasons why I love G2/G3 for IFB/scratch track feeds over Lectro or Zaxcom IFB solutions:
– The mini plug input/output is highly compatible without need for custom cables. You can feed a scratch track to  a Red Epic with a standard ipod cable. Transmitter Mic/line input selectable thru tip or ring on the cable. You can hook up to anything with a good set of adaptors. Have you sent audio to a Black Magic camera yet? Non-standard, strangely wired 1/4″ jack inputs, but no problem with a Senn and an ipod cable with a headphone adaptor.
– you can feed  hops and Ifb with same transmitter. 1 less frequency to coordinate.

-Less weight and RF mess in a sound bag. I’d rather carry around a 2 ounce, 30mw G3, than a 1/2 pound, 250mw flamethrower like the Lectro T4.

– I purchased my first set for scratch track hops in 2005. I now have 6 transmitters, 4 plugs, 6 receivers and 15 IFB’s. All purchased on ebay, and on average, less than half of retail. (Many misguided soundies and one-off project users buy these, then dump ’em. )

I’ve yet to have one break.  I’ve replaced many antennas at 5 bucks each, if you can solder well, you’re good.
– huge battery life. 3 days with a pair of lithium AA’s
-audio/rf metering on every unit
-Better range than lectro R1a or zax 2.4 gHz IFB units, owing to  external whip antennas
-transmitter won’t RF swamp a sound bag
-some venues now restricting 2.4 gHz devices as they compete with wifi (Zaxcom IFB)
-super wide input/output audio level settings. It’s easier to set the level on the Senn than dig around on the cryptic Red Epic’s audio screen. So why bother?
-instinctively intuitive to use. Big, understandable, backlit display
-great for feeding video assist, pa systems, or pulling feeds from PA or press feeds
velcro them together for 2 channels, and they are still a very small receiver pkg.
-They’re Great crash wireless for talent- (about the only time I’ll put one on a talent).
-30 mw is low for transmitter power, but as an IFB, the pack is not against somebody’s body.
Instead, it is out in free space on your cart or bag. So no RF absorption from a sweaty cast member’s body.

I’ve have found that the Lectro IFBs are better if your crew needs to change receiver channels frequently to listen to different sound units. WIth Lectro R1a’s, They just push the volume button to cycle thru programmed channels, without needing to look at it. (Don’t know if the ERX can do this).

-Senn’s butt-plug transmitters are also cheap and great for a quickn’dirty wireless handheld for PA or voice-of-god mic for AD’s

On a recent commercial, with one Senny transmitter, I fed scratchtrack to  two Alexas, video assist, client-lounge PA speaker and 15 IFB’s. Excellent range, kinda nice.
-iem headphone amp VERY loud. Even the regular receivers can drive a headphone at +6

-easy to coordinate freqs with internal pre-selects/rf metering, or use the freq finder app.

IEMs and beltpack receivers will also receive acceptable audio sent from more powerful lectro IFB transmitters.

-I could go on. I’ve got buckets of these things.

But I never will use them as frontline talent wireless. They breakup a little at high audio frequencies (sibilant sounds) unless you stay well within the headroom, like half-level.

-By Pete Verrando www.txsound.com

 

Sound Bag Abyss

deathSoundbagHow about an ongoing gallery of some of the more outrageous sound recording configurations for run-n-gun use? Such as the above. Is somebody supposed to wear this on their chest? Don’t forget the Ipad (right), which packs, oh, I don’t know. Where do we put the Ipad? Across the top. This rig is also good for lunch break, you can just eat right off the rig, you don’t even have to sit down. Throw a napkin down first, of course.

large production sound bag

Looks Great, Just don’t run.

heavy location sound bag

Nightmare location sound bag. Not mine.

large production sound bag mixer

backbrace not included, unlimited stern looks.

Video Blow Torch Transmitter Interference for Wireless Microphones

gx-68 wireless video transmitter swamps wireless mics

The GX-68 Swamping Video Transmitter from Canada.

Imagine yourself listening to your favorite music on an Ipod with some really nice headphones. Maybe those Bose Quiet-Comfort 15’s, my fave on airplanes. They really sound great.

Now imagine you’re at a Skrillex show, 1st row, next to a massive stack of loudspeakers, while still listening to your Ipod with those great Bose headphones. What? Can’t hear your Ipod? You might say you’ve been swamped or more technically, de-sensed. Your headphone audio can’t compete with a Skrillex speaker stack. Bass, highs, no matter. Can’t hear a thing. No matter how great those headphones are, Skrillex’s speakers are overwhelming them.

Skrillex is swamping your headphones. The only remedy is physical distance between you and Skrillex.

lectrosonics, scans, wireless microphones, interference

Various Lectro Scans…Top left- pretty swamped! Bottom right- wide open.

The whole hop affair requires robust, expensive wireless audio systems. But, like my Bose headphones, my fine audio receivers had to share 1st row with the blazing Skrillex video flamethrower, and were de-sensing as a result of the powerful RF eminating from said blowtorch. The receivers have a frequency scan function (Lectrosonics UCR411a), and it was showing complete RF obliteration with the video transmitter switched on. A solid black block, floor to ceiling. When a powerful RF transmitter comes shoulder-to-shoulder with an RF receiver, de-sensing happens. The trans RF overwhelms the circuitry in the receiver, regardless of frequency selected. The only cure is distance.

Move the transmitter 3 or 4 feet away, and everything’s OK! But the only place for the video transmitter and my receivers to live were on the side of the camera. So who’s problem is this? Why mine, of course! Camera and director could not work without the little wireless video system.

No problem, the director says! We’ll just go “hard wire” from sound to camera for the entire week. Dark storm clouds formed over my head, images of water skiing behind camera, with an audio-cable tow rope, inside a wrecked-out house. Outside of interviews and other “tame” shoots, the last time I went hard-wire to camera was probably sometime in 1998.

Cameraman: Works great at home, he says. You can take the camera home tonight and “work it out.”

Lectro Lectrosonics scan swamped

Another Swamped scan on a Lectro Receiver

So, my 1st day goes down with the cable tether, as the production was in 1st day freight-train mode, and no down time for a little audio troubleshooting. I trudge the camera home that evening to perform the “prep” that should have happened the day before the shoot. On the bench, I learn that the transmitter is tunable from 512 thru 800 mHz. From the internet I learn about the transmitter, specs & how to set the frequency, as camera dept. hadn’t a clue about their little black box. I try different combinations of transmitter and hop frequencies, looking for those that play well together. No go. The video transmitter swamps everything from Lectro Block 21 thru 26 and beyond, regardless of frequency setting.

I try some surgery on the video transmitter’s antenna, running a tightly looped wire around the antenna and soldering it to the BNC shell. This detuned the antenna to the point where it became a less effective radiator. However, this may make matters worse by raising the vSWR of the antenna, which may cause the transmitter case radiate RF, or even burn out the transmitter.

I finally mount the transmitter way forward on the camera, tucking the antenna under the viewfinder, and set it to 800 mHz (channel 69). I mount the audio receivers at the extreme rear of the camera, using Lectro block 21 (520 mHz). Doing a scan, this gets the swamping down to the 50% point on the scan display.

Using 100mw transmitter hops, I send audio to the camera and walk test it in the backyard. Amazingly, no dropouts or hits! The Lectro wireless are robust enough to deliver clean audio despite 50% RF interference levels on the receivers. This is using UCR411a Receivers. I’m not sure I could have accomplished the same feat with the less-robust Lectro UCR401 receivers, or SRa’s, which are the equivalent of 401’s. Looks like camera’s gonna have to lug around a little extra weight on the side!

Regardless, I keep a minimum distance from the camera throughout the week, to make sure those hops were solid. I also ran 24 bit backup audio files on everything. Camera dept. refused to do a free-run sync of timecode with my recorder, something to do with the antiquated notion that sequentially coded files digitize faster. No argument from me. If they need the backup, hello Plural Eyes.

Lessons learned! Good times!      by Pete Verrando www.txsound.com